The purpose of this systematic review and meta-analysis is to assess existing literature and determine the association between the Hounsfield unit (HU) value and the vertebral body quality (VBQ) score with mechanical complications (MCs) after adult spinal deformity (ASD) surgery. Although bone quality is considered an increasingly important factor for MCs after ASD surgery, the utility of the HU value assessed by computed tomography and the VBQ score assessed by magnetic resonance imaging remains unknown. A systematic review of PubMed, Embase, and Cochrane Library databases was performed to find studies evaluating the association between the HU value and the VBQ score with MCs after ASD surgery. In the subsequent meta-analysis, MC outcomes were combined using a random-effects model, and the standardized mean difference and 95% confidence interval were calculated. The final analysis included a total of 20 studies. Nineteen studies reported HU values, and two studies reported VBQ scores. Proximal junctional kyphosis/failure (PJK/PJF) was reported as the MC in 16 studies, whereas other MCs were included in 6 studies. Six studies with a pool of 506 patients with ASD revealed that preoperative HU values at the upper instrumented vertebra (UIV) and UIV+1 were significantly lower in patients with PJK/PJF (standardized mean difference, −0.74; 95% confidence interval, −1.09 to −0.40). Three studies suggested an cutoff HU value of approximately ≤120, yielding a pooled sensitivity of 0.77, specificity of 0.67, and diagnostic odds ratio of 7.01. However, two studies reported conflicting results on the relationship between the VBQ score and PJK/PJF. Low HU values predicted the risk of certain MCs, particularly PJK/PJF, after ASD surgery. An HU value of <120 should alert surgeons to be cautious about the postoperative occurrence of PJK/PJF. Future studies are needed to validate the cutoff HU value and evaluate the utility of the VBQ score.

Objective: While minimally invasive-transforaminal lumbar interbody fusion (MIS-TLIF) has shown superiority in key clinical metrics over the open approach, evidence regarding patient-reported outcomes remains limited. This study compared postoperative recovery trajectories and symptomatic improvement phases between MIS and open TLIF. Methods: This retrospective review included patients who underwent single-level MIS or open TLIF. Oswestry Disability Index (ODI) and Numerical Rating Scale (NRS) for back and leg pain were collected preoperatively and postoperatively. Segmented regression analysis with mixed-effects modeling, allowing for identification of distinct recovery phases, compared symptomatic trends between approaches. Results: Of 324 patients (268 MIS, 56 open), baseline demographics were similar except for greater preoperative leg pain in the MIS group (NRS: 6.0 vs. 5.0, p = 0.027). A segmented regression model identified 4 ODI recovery phases: postoperative disability phase (PDP, day 0 to 13), early improvement phase (day 13 to 28), late improvement phase (day 28 to 110), and plateau phase (later than day 110). The MIS group exhibited significantly lower disability exacerbation during PDP (β = 0.93 vs. 1.42 points per day, p = 0.008). Additionally, the plateau of NRS back occurred significantly earlier in the MIS group than in the open group (MIS, 26.7 ± 2.6 days vs. open, 51.7 ± 6.6 days, p < 0.001). Conclusion MIS-TLIF resulted in lower postoperative disability during the first 2 weeks compared to the open approach. Furthermore, low back pain achieved an earlier plateau in back pain by about 4 weeks in the MIS approach.

Objective: While minimally invasive-transforaminal lumbar interbody fusion (MIS-TLIF) has shown superiority in key clinical metrics over the open approach, evidence regarding patient-reported outcomes remains limited. This study compared postoperative recovery trajectories and symptomatic improvement phases between MIS and open TLIF. Methods: This retrospective review included patients who underwent single-level MIS or open TLIF. Oswestry Disability Index (ODI) and Numerical Rating Scale (NRS) for back and leg pain were collected preoperatively and postoperatively. Segmented regression analysis with mixed-effects modeling, allowing for identification of distinct recovery phases, compared symptomatic trends between approaches. Results: Of 324 patients (268 MIS, 56 open), baseline demographics were similar except for greater preoperative leg pain in the MIS group (NRS: 6.0 vs. 5.0, p = 0.027). A segmented regression model identified 4 ODI recovery phases: postoperative disability phase (PDP, day 0 to 13), early improvement phase (day 13 to 28), late improvement phase (day 28 to 110), and plateau phase (later than day 110). The MIS group exhibited significantly lower disability exacerbation during PDP (β = 0.93 vs. 1.42 points per day, p = 0.008). Additionally, the plateau of NRS back occurred significantly earlier in the MIS group than in the open group (MIS, 26.7 ± 2.6 days vs. open, 51.7 ± 6.6 days, p < 0.001). Conclusion MIS-TLIF resulted in lower postoperative disability during the first 2 weeks compared to the open approach. Furthermore, low back pain achieved an earlier plateau in back pain by about 4 weeks in the MIS approach.

Objective: While minimally invasive-transforaminal lumbar interbody fusion (MIS-TLIF) has shown superiority in key clinical metrics over the open approach, evidence regarding patient-reported outcomes remains limited. This study compared postoperative recovery trajectories and symptomatic improvement phases between MIS and open TLIF. Methods: This retrospective review included patients who underwent single-level MIS or open TLIF. Oswestry Disability Index (ODI) and Numerical Rating Scale (NRS) for back and leg pain were collected preoperatively and postoperatively. Segmented regression analysis with mixed-effects modeling, allowing for identification of distinct recovery phases, compared symptomatic trends between approaches. Results: Of 324 patients (268 MIS, 56 open), baseline demographics were similar except for greater preoperative leg pain in the MIS group (NRS: 6.0 vs. 5.0, p = 0.027). A segmented regression model identified 4 ODI recovery phases: postoperative disability phase (PDP, day 0 to 13), early improvement phase (day 13 to 28), late improvement phase (day 28 to 110), and plateau phase (later than day 110). The MIS group exhibited significantly lower disability exacerbation during PDP (β = 0.93 vs. 1.42 points per day, p = 0.008). Additionally, the plateau of NRS back occurred significantly earlier in the MIS group than in the open group (MIS, 26.7 ± 2.6 days vs. open, 51.7 ± 6.6 days, p < 0.001). Conclusion MIS-TLIF resulted in lower postoperative disability during the first 2 weeks compared to the open approach. Furthermore, low back pain achieved an earlier plateau in back pain by about 4 weeks in the MIS approach.

Objective: While minimally invasive-transforaminal lumbar interbody fusion (MIS-TLIF) has shown superiority in key clinical metrics over the open approach, evidence regarding patient-reported outcomes remains limited. This study compared postoperative recovery trajectories and symptomatic improvement phases between MIS and open TLIF. Methods: This retrospective review included patients who underwent single-level MIS or open TLIF. Oswestry Disability Index (ODI) and Numerical Rating Scale (NRS) for back and leg pain were collected preoperatively and postoperatively. Segmented regression analysis with mixed-effects modeling, allowing for identification of distinct recovery phases, compared symptomatic trends between approaches. Results: Of 324 patients (268 MIS, 56 open), baseline demographics were similar except for greater preoperative leg pain in the MIS group (NRS: 6.0 vs. 5.0, p = 0.027). A segmented regression model identified 4 ODI recovery phases: postoperative disability phase (PDP, day 0 to 13), early improvement phase (day 13 to 28), late improvement phase (day 28 to 110), and plateau phase (later than day 110). The MIS group exhibited significantly lower disability exacerbation during PDP (β = 0.93 vs. 1.42 points per day, p = 0.008). Additionally, the plateau of NRS back occurred significantly earlier in the MIS group than in the open group (MIS, 26.7 ± 2.6 days vs. open, 51.7 ± 6.6 days, p < 0.001). Conclusion MIS-TLIF resulted in lower postoperative disability during the first 2 weeks compared to the open approach. Furthermore, low back pain achieved an earlier plateau in back pain by about 4 weeks in the MIS approach.

Objective: While minimally invasive-transforaminal lumbar interbody fusion (MIS-TLIF) has shown superiority in key clinical metrics over the open approach, evidence regarding patient-reported outcomes remains limited. This study compared postoperative recovery trajectories and symptomatic improvement phases between MIS and open TLIF. Methods: This retrospective review included patients who underwent single-level MIS or open TLIF. Oswestry Disability Index (ODI) and Numerical Rating Scale (NRS) for back and leg pain were collected preoperatively and postoperatively. Segmented regression analysis with mixed-effects modeling, allowing for identification of distinct recovery phases, compared symptomatic trends between approaches. Results: Of 324 patients (268 MIS, 56 open), baseline demographics were similar except for greater preoperative leg pain in the MIS group (NRS: 6.0 vs. 5.0, p = 0.027). A segmented regression model identified 4 ODI recovery phases: postoperative disability phase (PDP, day 0 to 13), early improvement phase (day 13 to 28), late improvement phase (day 28 to 110), and plateau phase (later than day 110). The MIS group exhibited significantly lower disability exacerbation during PDP (β = 0.93 vs. 1.42 points per day, p = 0.008). Additionally, the plateau of NRS back occurred significantly earlier in the MIS group than in the open group (MIS, 26.7 ± 2.6 days vs. open, 51.7 ± 6.6 days, p < 0.001). Conclusion MIS-TLIF resulted in lower postoperative disability during the first 2 weeks compared to the open approach. Furthermore, low back pain achieved an earlier plateau in back pain by about 4 weeks in the MIS approach.